Brightness automatically adjusting system and method for adjusting brightness thereof

Abstract

A brightness adjustment system includes a camera, a computer, and a liquid crystal display. The liquid crystal display includes a signal processor, a backlight control circuit and a backlight unit. The camera captures environmental images and sends the environmental image to the computer. The computer analyzes the environmental image to obtain a environmental brightness and sends a control signal to the signal processor according to the environmental brightness. The signal processor receives the control signal and sends an adjusting signal to the backlight unit according to the control signal. The backlight control circuit adjusts a brightness of the backlight unit according to the adjusting signal. A method of automatically adjusting brightness of a liquid crystal display is also provided.

1 . A brightness adjustment system comprising:
 a camera;   a computer; and   a liquid crystal display comprising a signal processor, a backlight control circuit, and a backlight unit,   wherein the camera captures an environmental image and sends the environmental image to the computer, the computer analyzes the environmental image to obtain a environmental brightness and sends a control signal to the signal processor according to the environmental brightness, the signal processor receives the control signal and sends an adjusting signal to the backlight unit according to the control signal, and the backlight control circuit adjusts a brightness of the backlight unit according to the adjusting signal.   
     
     
         2 . The brightness adjustment system of  claim 1 , wherein the camera is connected to the computer via a universal serial bus (USB) interface. 
     
     
         3 . The brightness adjustment system of  claim 1 , wherein the camera is positioned inside the liquid crystal display. 
     
     
         4 . The brightness adjustment system of  claim 1 , wherein a look up table in firmware of the signal processor stores a number of adjustment commands, and the signal processor compares a received command from the computer with the look up table to judge if the received command is valid. 
     
     
         5 . The brightness adjustment system of  claim 1 , wherein the computer defines several areas on the environmental image and respectively analyzes the several areas of the environmental image to obtain a brightness information of the environmental image. 
     
     
         6 . The brightness adjustment system of  claim 5 , wherein the several areas are circular areas, the computer calculates an average brightness of the several circular areas and defines the average brightness as the environmental brightness. 
     
     
         7 . The brightness adjustment system of  claim 6 , wherein the computer calculates a difference between the environmental brightness and a brightness of the liquid crystal display. 
     
     
         8 . The brightness adjustment system of  claim 7 , wherein the signal processor adjusts the brightness of the backlight unit according to the difference between the environmental brightness and a brightness of the liquid crystal display. 
     
     
         9 . The brightness adjustment system of  claim 1 , wherein the backlight unit is a cold cathode decoration lamp (CCFL) or a light emitting diode (LED). 
     
     
         10 . A method of automatically adjusting brightness of a liquid crystal display comprising:
 capturing an environmental image;   analyzing the environmental image to obtain environmental brightness;   obtaining a brightness of the liquid crystal display;   comparing the environmental brightness with the brightness of the liquid crystal display and generating a control signal according to a comparison result;   generating an adjusting signal according to the control signal; and   adjusting the brightness of the liquid crystal display according to the adjusting signal.   
     
     
         11 . The method of  claim 10 , wherein the environmental image is captured by a web camera or a digital camera. 
     
     
         12 . The method of  claim 11 , wherein the camera has a universal serial bus interface. 
     
     
         13 . The method of  claim 11 , wherein the camera is positioned inside the liquid crystal display. 
     
     
         14 . The method of  claim 11 , wherein several areas are defined on the environmental image for obtaining the environmental brightness. 
     
     
         15 . The method of  claim 14 , wherein the several areas are circular areas, and an average brightness of the several circular areas is calculated and defined as the environmental brightness. 
     
     
         16 . The method of  claim 11 , wherein the comparison result is a difference of the environmental brightness and the brightness of the liquid crystal display. 
     
     
         17 . The method of  claim 16 , wherein when the environmental brightness exceeds that of the liquid crystal display, the brightness of the liquid crystal display is increased to equal the environmental brightness. 
     
     
         18 . The method of  claim 16 , wherein when the environmental brightness is less than the brightness of the liquid crystal display, the brightness of the liquid crystal display is decreased to equal the environmental brightness. 
     
     
         19 . The method of  claim 11 , further comprising determination of whether the adjusting signal is valid. 
     
     
         20 . The method of  claim 19 , wherein a look up table is used to judge whether the adjusting signal is valid.